1. Field of the Invention
The present invention relates to a technical field of a substrate treatment apparatus and a substrate treatment method using a module performing a solution treatment and a module performing ultraviolet irradiation on a substrate.
2. Description of the Related Art
In a photoresist step that is one of semiconductor manufacturing steps, resist is supplied to the front surface of a semiconductor wafer (hereinafter, referred to as a wafer) and exposed into a predetermined pattern and then developed to form a resist pattern. The formation of the resist pattern is performed by a system in which an exposure apparatus performing exposure processing is connected a coating and developing apparatus performing a forming treatment and a developing treatment of various kinds of coating films such of resist and the like.
As one module provided in the coating and developing apparatus, there is an edge exposure module that exposes an edge portion of the wafer after the resist film is formed thereon so as to prevent the resist film at the edge portion outside a pattern region of the wafer from remaining. This module is to irradiate the edge portion of the wafer with an ultraviolet ray using, for example, a mercury lamp, a xenon lamp or the like. Because of an operating life of the lamp, time to change the lamp is decided so that an alarm is outputted when the change time comes and the lamp is changed.
On the other hand, it is studied that a unit block including the edge exposure module and the like is made duplex to be able to continue treatments on wafers even when maintenance such as the change of lamp is being performed (Japanese Laid-open Patent Publication No, 2008-277528). In this case, the wafers are distributed and carried to both unit blocks, and when maintenance is performed on one unit block, or when a trouble has occurred in one unit block, the other unit block can be used as described in Japanese Laid-open Patent Publication No. 2009-278138.
Incidentally, after a lapse of the operating life of the lamp, the lamp cannot be used at all any longer, so that the wafers for which the treatments for forming a coating film before exposure cannot be passed to the downstream side and those remaining wafers should be collected, resulting in a reduced operating efficiency of the apparatus. On the other hand, because of variations in operating life of individual lamps, the time to change the lamp is set to the time earlier than the actual end of the operating life in consideration of a margin. Therefore, the running cost of the edge exposure module becomes high and the maintenance frequency is also high. It is also known that when the illuminance of the lamp has decreased, the edge exposure is performed with an exposure time increased according to the amount of decrease (integrated exposure), but when the lamp reaches the end of the operating life and its illuminance is below the lower limit, the wafers for which the above treatments are being performed cannot be passed any longer and the integrated exposure is a cause of decreasing the throughput because of long processing time.
Further, the processing of irradiating the substrate such as a wafer or the like with an ultraviolet ray includes processing of removing an organic substance and processing of improving the quality of an insulating film such as a silicon oxide film other than the edge exposure. The ultraviolet irradiation module performing such processing is sometimes arranged in a block including a carry path together with, for example, a module performing single wafer cleaning and a chemical coating module for a silicon oxide film. This case also has the same problems as those in the above.